Sounds like you didn't finish filing. Just paying the fees does not file the return. You had to continue on and hit the big orange Transmit Returns Now button. Then you would get 2 more emails saying it was Transmitted and another email saying if it was Accepted or Rejected.
You have to print it out and mail it now. Or finish it and mail.
How to finish a prior year online return
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-...
